*{
    box-sizing: border-box;
}
html{
    height: 100vh;
}
body{
    margin: 0;
}
nav{
    text-align: center;
}
main{
    display: flex;
    justify-content: center;
}
p{
    font-size: 46px;
    font-weight: bolder;
    text-transform: capitalize;
}
.letterS:hover{
    transform:rotateY(180deg);
    transition: 2s letterS;
}